• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.259-272
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• 2020

Nowadays, two types, Yumhae and Sikhae methods, remained as traditional seafood fermentation methods in Korea. In this study, flavor compounds in two types of salt-fermented fishes made by Yumhae method such as anchovy Engraulidae sp., shrimp Caridea sp., squid Decapodiformes sp., big eyed herring Clupea sp., gizzard shad Dorosoma sp. and hairtail Trichiurus sp., and made by Sikhae method such as Alaska pollack Gadus Chalcogrammus and squid. Volatile compounds detected in all salt-fermented fishes were composed mainly of aldehydes (45), ketones (39), alcohols (45), acids (12), esters (47), N-containing compounds (43), aromatic hydrocarbons (37), S-containing compounds (26), furans (10), and miscellaneous compounds (40) in salt-fermented fishes made by Yumhae method. Meanwhile, alcohols (47), terpenes (38), S-containing compounds (22), carbonyl compounds (19 aldehydes, 18 ketones), esters (13), and acids (14). Aroma-active compounds were identified by Gas chromatography/mass spectrometry/olfactometry and aroma extract dilution analysis in salt-fermented anchovy, shrimp and tuna (Thunnini sp.) sauce. Ethyl 2-methylbutanoate (candy/sweet) and 2-ethyl-3,5-dimethylpyrazine (nutty/baked potato-like) were predominant odorants in salt-fermented anchovy, whereas dimethyl trisulfide (cooked cabbage/soy sauce-like), 2-ethyl-3,5-dimethylpyrazine, and (E,E)-2,4-heptadienal (fatty/grainy) in salt-fermented shrimp, and dimethyl trisulfide, 3-methylbutanal (dark chocolate-like), and 3-methylthiopropanal (baked potato-like) in tuna sauce.

• Nuclear Engineering and Technology
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• v.52 no.2
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• pp.223-229
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• 2020

The present work proposes a solution to the static Boltzmann transport equation approximated by the simplified P₃ (SP₃) on angular, and the analytic coarse mesh finite difference (ACMFD) for spatial variables. Multi-group SP₃-ACMFD equations in 3D rectangular geometry are solved using the GMRES solution technique. As the core time dependent analysis necessitates the solution of an eigenvalue problem for an initial condition, this work is hence devoted to development and verification of the proposed static SP₃-ACMFD solver. A 3D multi-group static diffusion solver is also developed as a byproduct of this work to assess the improvement achieved using the SP₃ technique. Static results are then compared against transport benchmarks to assess the proximity of SP₃-ACMFD solutions to their full transport peers. Results prove that the approach can be considered as an acceptable interim approximation with outputs superior to the diffusion method, close to the transport results, and with the computational costs less than the full transport approach. The work would be further generalized to time dependent solutions in Part II.

• Journal of Korean Society of Transportation
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• v.10 no.3
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• pp.21-42
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• 1992

As for the travel demand analysis of the past, forcasting has been conducted by the use of revealed preference(RP) informations about actual or observed choices made by individuals. Forcasting method using RP data needs implicit assumptions that there will be no remarkable changes in existing transport conditions. However in case of occuring the great changes in existing conditions or adding a new choice-set of hypothetical options, it is very difficult to predict future travel demand. Fortunately in recent years, especially in the mode choice analysis, it has been perceived that the importance of individual performance data using stated preference(SP) experiments as well as RP data. But the research reports has not been reported sufficiently from models estimated using SP data. Under this background, we analyze the factors affecting the mode choice behavior as a fundamental study against the modelling task with SP choice data. For this analysis, we assumed subway operations in the secondary cities where there are no subway lines until now, and set up a choice-set of hypothetical options based on Experimental Design Method.

• The Korean Journal of Pain
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• v.9 no.2
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• pp.326-335
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• 1996

Background: Though a number of studies have described the distribution of substance P(SP)-like immunoreactivity in the spinal cord, they have been focused on lamina I and II of the dorsal horn and there are little morphological studies on the topographic distribution and ultrastructure of the SP immunoreactive neurons especially in the ventral horn of the spinal cord. this study was conducted to identify distribution pattern of SP immunoreactive neurons and to difine the synaptic organization of their processes in ventral horn of the thoracic cord of the cat by preembbeding immunocytochemical method using SP antiserum. Methods: Five adults cats of either sex were used and deeply anesthetized by intramuscular injection of ketamine. After removal of the spinal cord, samples of thoracic cord were taken and placed in fresh fixative at $4^{\circ}C$ for 2 hours. Transverse sections $50{\mu}m$ thick were processed using the preembbeding immunocytochemical method and incubated consecutively in the specific primary antibody and the 10% normal goat serum, the rabbit anti-substance P antiserum, the biotin-labelled goat anti-rabbit IgG and finally the avidin-biotin-peroxidase complex. The processed tissue sections were throughly washed and stained in the black with 1% uranyl acetate. Section were examined on a electron microscope. Results: 1) SP immunoreactive neurons were observed in the gray matter around central canal. 2) In lamina I and II SP immunoreactivity was observed in both myelinated and unmyelinated nerve fibers, but in ventral horn only in the unmyelinated nerve fibers. 3) SP immunoreactive axon terminals with small round and large dense core vesicles made chemical synapses onto the dendrites of motor neurons in the ventral horn. Conclusion: SP immunoreactive neurons might play an important role in modulation of motor neurons in the ventral horn of the thoracic cord of the cat.

• Korean Journal of Microbiology
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• v.7 no.1
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• pp.41-44
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• 1969

A new method for manufacturing the active seed starter (Korean Kok-Ja) has been studied, designed new method consists of the boiling process of raw wheat material and pure culture process of Rhizopus fungi. The feasibility study for industrialization of these methods have been performed, the liquefying and saccharifying activities were put to analysis and compared with conventional product of Kok-Ja. The isolated strains of mold from raw wht and Kok-Ja were idetified as Rhizopus sp., Aspergillus sp., Aspergillus niger sp., Endomyces sp., and Fungi imperfecii. It is proved that the saccharifying and liquefying activities are much stronger than that of conventional product of Kok-Ja, and the growth of Rhizopus strain in boild what material are vigorous than that of old type Kok-Ja. Then it is considered the newly designed method is effective to manufacturing a fine better Kok-Ja.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.4
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• pp.75-82
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• 2021

The objective of this study is to examine the loss of prestressing stress in the developed prestressing reinforcing units using steel bar and pipe (SP). The main parameters were the reinforcing bar type, the magnitude of prestressed force, and prestressing method. The test results showed that the loss of prestressing stress for SP was highest in the initial prestressing step, which was higher for the compression introduction typed specimens than tension introduction typed specimens. The loss of prestressing stress of SP made with P800 was 1.6% for the compression introduction typed specimen with 0.8f_y, which was lowest than the other specimens. Meanwhile, the relaxation of SP with the respect to the time ranged between 0.4 and 1.9%, irrespective of SP material type, the magnitude of prestressed force, and prestressing method. These values were less than 2.5%, which is the maximum value for the relaxation of prestressed reinforcing steel bars in design codes. Consequently, considering the loss of stress developed in the initial prestressing step, the developed SP material type, prestressing introduction method, and magnitude are recommended to be P800, compression introduction type, and 0.8f_y.

• KSBB Journal
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• v.15 no.2
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• pp.150-155
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• 2000

Antioxidative activity of c비ture of Streptomyces sp. BH-405 was investigated. After removal of pellets of Streptomyces sp. B BH-405, antioxidative substances were is미ated and suc$\infty$sively purified from culture of Streptomyces sp. BH-405 by by thin | layer chromatography $\pi$LC) or silica gel column chromatography. The fraction 3 obtained from ethylether fractionation of the C culture appeared highest level of anti oxidative activity as determined by thiocyanate method. Band 2 obtained by further P purification of this fraction showed higher anti oxidation level than that of same concentration of dl- $\alpha$ -tocopherol, butylated h hydroxy anisole (BHA). The band 2 showed higher rate of 1, 1.diphenyl 2-picrylhydrazyl (DPPH) decolorization than dl-$\alpha$-tocopherol. In the rat liver microsomes, band 2 rapidly inhibited lipid peroxidation which was initiated enzymatically by r reduced nicotinamide adenine dinucleotide phosphate (NADPH) or non-enzymatically by Fenton’s reagent. Band 2 inhibited on | lipid peroxidation of mitochondria or the linoleic acid hydro peroxide induced peroxidation system. It is concluded that band 2 obtained by fractionation of Streptomyces sp. BH-405 cultivation contained antioxidants with the capacity to inhibit oxidative m modification.

• Journal of KIISE:Databases
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• v.32 no.3
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• pp.254-262
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• 2005

This paper presents a new sequential indexing method called segment-page indexing (SP-indexing) for multidimensional range queries. The design objectives of SP-indexing are twofold:(1) improving the range query performance of multidimensional indexing methods (MIMs) and (2) providing a compromise between optimal index clustering and the full index reorganization overhead. Although more than ten years of database research has resulted in a great variety of MIMs, most efforts have focused on data-level clustering and there has been less attempt to cluster indexes. As a result, most relevant index nodes are widely scattered on a disk and many random disk accesses are required during the search. SP-indexing avoids such scattering by storing the relevant nodes contiguously in a segment that contains a sequence of contiguous disk pages and improves performance by offering sequential access within a segment. Experimental results demonstrate that SP-indexing improves query performance up to several times compared with traditional MIMs using small disk pages with respect to total elapsed time and it reduces waste of disk bandwidth due to the use of simple large pages.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.244-251
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• 2015

BACKGROUND: Recent studies have described the importance of bacteria that can degrade polycyclic aromatic hydrocarbons (PAHs). Here we screened bacterial isolates from commercial gasoline for PAH degraders and characterized their ability to degrade PAHs, lipids and proteins as well as their enantioselective epoxide hydrolase activity, salt tolerance, and seawater survival. METHODS AND RESULTS: One hundred two bacteria isolates from commercial gasoline were screened for PAH degraders by adding selected PAHs on to the surface of agar plates by the sublimation method. A clear zone was found only around the colonies of PAH degraders, which accounted for 13 isolates. These were identified as belonging to Bacillus sp., Brevibacterium sp., Micrococcus sp., Corynebacterium sp., Arthrobacter sp., and Gordonia sp. based on 16S rRNA sequences. Six isolates belonging to Corynebacterium sp., 3 of Micrococcus sp., Arthrobacter sp. S49, and Gordonia sp. H37 were lipid degraders. Arthrobacter sp. S49 was the only isolate showing high proteolytic activity. Among the PAH-degrading bacteria, Arthrobacter sp. S49, Brevibacterium sp. S47, Corynebacterium sp. SK20, and Gordonia sp. H37 showed enantioselective epoxide hydrolase activity with biocatalytic resolution of racemic styrene oxide. Among these, highest enantioselective hydrolysis activity was seen in Gordonia sp. H37. An intrinsic resistance to kanamycin was observed in most of the isolates and Corynebacterium sp. SK20 showed resistance to additional antibiotics such as tetracycline, ampicillin, and penicillin. CONCLUSION: Of the 13 PAH-degraders isolated from commercial gasoline, Arthrobacter sp. S49 showed the highest lipid and protein degrading activity along with high active epoxide hydrolase activity, which was the highest in Gordonia sp. H37. Our results suggest that bacteria from commercial gasoline may have the potential to degrade PAHs, lipids, and proteins, and may possess enantioselective epoxide hydrolase activity, high salt tolerance, and growth potential in seawater.

• Journal of Microbiology and Biotechnology
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• v.6 no.5
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• pp.358-360
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• 1996

Solvent extraction, soxhlet method, and supercritical fluid extracion were considered, respectively, as the method of choice for the recovery of DHA from lyophilized Thraustochitrium sp., and the results of corresponding extraction were compared. Supercritical fluid extraction seems to be the most appropriate process with respect to time, process simplicity, and extractant intoxicity.